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JPA Doc
14

javax.persistence.criteria.Subquery

a subquery root correlated to a root of the enclosing query. Create a subquery root correlated to a root of the enclosing query. Parameters: parentRoot - a root of the containing query Returns: subquery ... correlated to a join object of the enclosing query. Create a subquery join object correlated to a join object
Forum
14

JPA Query language support in OBjectDB / Sub query or nested Query

have given a sample typed query below which fails to work with ObjectDB and it runs very well with the Hibernate/MySQL JPA. We are using Spring Data here. It looks like a problem with Sub query or nested queries where I am using IN clause like below. @Query("SELECT product FROM Product product
Manual
14

Retrieving JPA Entity Objects

object. Retrieval by Query The most flexible method for retrieving objects from the database is to use queries. The official query language of JPA is JPQL (Java Persistence Query Language). It enables retrieval of objects from the database by using simple queries as well as complex, sophisticated ones
Tutorial
14

Step 3: Add a Main Class

(); // Find the number of Point objects in the database: Query q1 = em.createQuery("SELECT COUNT(p ... ()); // Find the average X value: Query q2 = em.createQuery("SELECT AVG(p.x) FROM Point p ... objects from the database: TypedQuery query = em.createQuery("SELECT p
Tutorial
14

Step 3: Add a Main Class

: Query q1 = em.createQuery("SELECT COUNT(p) FROM Point p"); System.out.println("Total Points: " + q1.getSingleResult()); // Find the average X value: Query q2 = em ... > query =  em.createQuery("SELECT p FROM Point p", Point.class); List results
JPA Doc
14

javax.persistence.EntityManager

key, and to query over entities. The set of entities that can be managed by a given EntityManager ... database. Since: JPA 1.0 See Also: Query TypedQuery CriteriaQuery PersistenceContext Learn how to use ... on the EntityManager instance and any Query and TypedQuery objects obtained from it will throw
Issue
13

Once served to JSF page via @EJB query bean, many list fields are null (but same query ok after fresh persist in @PostConstruct)

, the inability to robustly query relationship fields in a web application renders the ObjectDB ... showing the query result in indexTest.xhtml. The problems is illustrated by running the attached JavaEE ... . For a number of different List fields, a query performed immediately after creating and persisting
Manual
12

Deleting JPA Entity Objects

of that object from the database. DELETE Queries DELETE queries provide an alternative way for removing entity objects from the database. Deleting objects using a DELETE query may be useful especially when many entity objects have to be deleted in one operation. The DELETE Queries in JPA/JPQL in chapter 4 explains how to use JPA DELETE queries.
FAQ
12

Is ObjectDB better than competing object databases?

queries (max, min, count, sum and avg). ObjectDB supports rich queries, including aggregate queries, as part of its support of JPQL (JPA Query Language) and JDOQL (JDO Query Language). ObjectDB is faster than other products.
Manual
12

Updating JPA Entity Objects

support. UPDATE Queries UPDATE queries provide an alternative way for updating entity objects in the database. Modifying objects using an UPDATE query may be useful especially when many entity objects have to be modified in one operation. The UPDATE Queries in JPA/JPQL in chapter 4 explains how to use JPA UPDATE queries.